In present-day aircraft construction, fuselage sections are still predominantly produced from metal materials, for example from materials comprising aluminium alloys or titanium alloys. Providing a round return for electrical consumers, safeguarding adequate lightning protection, and creating an adequate shielding effect vis-à-vis high-frequency electromagnetic interference radiation, do not pose a significant problem in such aircraft fuselages that are essentially purely made from metal, because the electrically adequately conductive exterior skin of the fuselage section can itself be used as a ground return for electrical consumers, and furthermore provides adequate protection vis-à-vis atmospheric high-voltage discharge, for example lightning strikes, and moreover also provides an adequate shielding effect vis-à-vis electromagnetic interference radiation.
In particular for reasons relating to saving weight, and to more favourable corrosion behaviour in the long term, and to the associated reduced maintenance and operating expenditure, in modern aircraft construction the use of composite materials, for example carbon-fibre-reinforced epoxy resins (CFRP materials), is increasingly common in the production of aircraft fuselage sections and of effective aerodynamic surfaces. However, carbon-fibre-reinforced epoxy resins are associated with a disadvantage in that they provide limited electrical conductivity, which requires additional measures for lightning protection and ground return of electrical consumers.
In order to achieve the required limited conductivity for ground return and in order to ensure the necessary lightning protection, from the state of the art it is known to arrange metal ground return rails by means of suitable fastening elements on the inside of the aircraft fuselage cell constructed with fibre composite materials. However, such ground return rails increase the weight of the aircraft fuselage section, without, however, substantially contributing to improved structural strength.